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Does The Washington Post Want You to Burn?
Trevor Butterworth, April 16,
A one-source story makes for incendiary reporting on mattresses safety.  

The Washington Post is basking in the glow of winning six Pulitzer prizes, which is great. Everyone here at STATS has been published in the Post at some point in their careers and we’re thrilled for all the reporters and editors who worked so hard on so many stories. What we’re not so thrilled about is that the Post also seems to want us to bask in a different kind of glow – the kind that we’d see just before being incinerated or suffocated.

It would appear that not everyone on the Post’s staff has heard of flashover. Flashover occurs when something soft and warm – say a mattress - catches fire and the heat from the fire causes everything else in the room to spontaneously ignite within minutes.

According to the Consumer Product Safety Commission (CPSC), flashover accounts for nearly all the deaths that occur outside the bedroom and half that occur inside the bedroom. Given that flashover happens when a mattress fire begins emitting heat of 1,000 kilowatts, something that, shockingly, can happen in under five minutes, the CPSC imposed new fire safety standards in 2007 that requires the heat emitted from a mattress fire to stay at 200 kilowatts for 30 minutes, thereby giving people a much greater chance to escape. The CPSC estimates that the new standards will save up to 270 lives each year

None of this was mentioned by the Post in an article which claimed, as the headline put it, that “Your mattress might be an environmental nightmare.

”Most mattresses, as well as memory foam and egg-crate covers, are made with petroleum-based ingredients such as polyurethane foam, which can emit a strong smell because of organic solvents. And most also contain flame retardants, required by fire-safety laws but often harmful to human health. In 2005, toxic fireproofing chemicals called polybrominated diphenyl ethers (PBDEs) were phased out of production, but some of their replacements are almost as bad, says Sonya Lunder, a senior analyst at the Environmental Working Group, a D.C.-based nonprofit organization.

Just how hazardous can a mattress -- or pad or pillow -- be? The answer might be enough to make you lose sleep. Regular tossing and turning causes a mattress's foam to break down, and the resulting dust can float into the air you breathe. A 2006 Consumer Product Safety Commission study estimated that the average adult sleeping on a conventional mattress will be exposed to 0.802 milligrams of antimony and 0.081 milligrams of boric acid -- which is commonly used to kill cockroaches -- every night.

To say that this story is a misleading reading of the CPSC’s Quantitative Assessment of Potential Health Effects From the Use of Fire Retardant (FR) Chemicals in Mattresses is an understatement (the Post didn’t link to the document so that readers could examine the risk assessment for themselves but restricted its link to a search of Post articles on the CPSC). According to the CPSC, the average daily dose of antimony from all exposure routes is 0.802 milligrams. (Table 16, page 45)

The CPSC calculated an acceptable daily intake (ADI) for antimony of 2.3 milligrams per kilo of bodyweight per day. (The acceptable daily intake is the amount of a substance that can be ingested per day over a lifetime without causing harm. The ADI includes a margin of safety which is usually a factor of 100 as is the case with antimony.)

So let’s count these figures out: 0.802 milligrams is the same as 802 micrograms. 2.3 milligrams equals 2,300 micrograms. For an average person weighing 70 kilos, the ADI for antimony is, therefore, 161,000 micrograms.

In tests, the CPSC found that after hitting a mattress 100,000 times to simulate wear and tear, a twin mattress would release a total of 210 micrograms of antimony over ten years.
Should this be something, as the Post claims, to lose sleep over?

To gauge the total risks, the CPSC created a combined hazard index (HI) for all routes of exposure. A hazard index of 1.0 or below does not indicate any adverse health effect for noncancer endpoints. As the Environmental Protection Agency notes, “a respiratory HI greater than 1.0 can be best described as indicating that a potential may exist for adverse irritation to the respiratory system. The CPSC found the HI was 0.005 for adults and 0.01 for children, which is to say, it found no risk.

As for cancer, the estimated risk for antimony was 0.027 cases per million over the course of 70 years for adults and 0.037 cases per million for children over the course of 70 years. Again, this is so staggeringly low as to be, effectively, non-existent. The benchmark for concern is 1 in a million or higher over 70 years.

Similar analyses and calculations were conducted on Boric Acid, with similar conclusions: there is no evidence of a risk to health. STATS confirmed these findings and what they meant for exposure risks with Dr. Treye Thomas, a toxicologist with the CPSC.

Unfortunately, because the Washington Post chose to rely on just one source – an environmental activist group – for guidance in reading the numbers, the article conveys risks that are not borne out by analysis or evidence. The Post contends that

The [CPSC]  report deems these amounts safe for those older than 5, but numerous studies have linked both substances to a host of adverse health effects at various doses, and the cumulative effect of daily exposure is unknown.

A search of the PubMed database turned up little to support either the contention that there are numerous studies or that there is substantial evidence of risk. There is some research showing possible risks for workers exposed to high levels of antimony – much higher than normal environmental exposure, which is why the National Toxicology Program is presently conducting a study on such risks.

In covering stories like this, journalists need to be cognizant that eliminating one risk can increase another. In this case, the Post neither considered the weakness of the evidence for antinomy in mattresses posing any sort of health risk (something which would have been apparent if the Post had followed the numbers) nor considered the risk that scaring people about mattresses could in fact lead to actual deaths.


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